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All posts created by debbie

| posted 19 Oct, 2019 00:17
That would be great!
debbie
Posted in: Cluster AR Annotation Tipsnon SEA-PHAGES genomes
| posted 18 Oct, 2019 01:19
Hi! Yes, ArV1 is the phage of that paper. Why do you say that AR phages are siphoviridae?
debbie
Posted in: Cluster AR Annotation Tipsnon SEA-PHAGES genomes
| posted 03 Oct, 2019 15:57
Amy,
I am the one QCing this genome and I have not gotten to it yet. Welkin, would you respond to the intron question?

I think that info that may be helpful is found here https://seaphages.org/forums/topic/4926/?page=1#post-7336
Thanks,
debbie
Edited 03 Oct, 2019 17:06
Posted in: Frameshifts and IntronsFinding introns
| posted 27 Sep, 2019 05:14
Hi all,
Recently Krista Freeman, a post doc in the Hatfull lab, and Julia Kovalski, an undergrad designed primers for 60 cluster/subclusters of mycobacteriophages. These primers were designed for verification of phage lysates in the Hatfull lab (and not to prematurely assign cluster designations to unsequenced phages). Attached is an Excel sheet of the primers/phages. Krista thought having the fasta files of the phages would be helpful. I thought adding a picture of Julia and Krista would be fun!
Edited 27 Sep, 2019 05:15
Posted in: Phage BiologyPCR Primers
| posted 25 Sep, 2019 20:50
A lot of Cluster EA1s have a tRNA in the middle of a middle tail gene. since you can only call one or the other, call the minor tail gene!
Posted in: Cluster EA Annotation TipstRNA in Cluster EA
| posted 25 Sep, 2019 18:40
If one looks at the immunity repressor of Cluster F1s like Mycobacteriophage Strokeseat, the coding potential data is confusing. The Starterator data clearly shows only 1 start that is found in all pham members.
The start in Strokeseat is at position 34251 (stop is at 33682).(gene length is 570bp).

This then provides adequate (just barely) space for promoters for this gene (CRO) and the next one (because they are transcribed in opposite directions). The start of this gene is at 34358 (stop is at 34651).
Hope you find this helpful!

Unfortunately, as is the nature of Cluster F1s, not all F1s have these phams.
Edited 08 Aug, 2023 13:20
Posted in: Cluster F Annotation TipsImmunity Repressor and CRO starts
| posted 31 Jul, 2019 20:07
Jordan (and anyone else who reads this terrific post,
I asked Chris Shaffer if I was correct in thinking that start 1 and 2 in the phamerator report 19534 were basically the same. He explained that they ARE the same. Check it out! chris just showed me that I am smarter than a computer! lol!

Deb,
what an interesting case,

TL,DR: no starts 1 and 2 are not really different even though starterator says they are.

Long version if interested:
this is a weird corner case where the starterator program is giving the literally correct answer which is really "wrong". So no the 1 and 2 should not be considered different. Looking very closely at the diagram you can see all the 1 starts have a tiny white sliver on the right edge while all the 2 starts do not. Here is the actual multiple sequence alignment (MSA) and you can see the single A base insertion in some sequence and not others (the while sliver represents the gap), I highlighted the start codon in yellow (attached):

When you ask a computer are those starts "the same" the answer is no, so Starterator considers the top 3 sequences as start 2 and the bottom 4 as start 1. What we have run across is one of the fundamental problems of MSA's, multiple sequence aligners like clustal just doesn't have any way to know if it should align as -A or A-. This is why people "hand tweek" alignments when they want the best possible alignments (for publishing conserved domains for example) because it just isn't possible to code in the external evidence needed to decide between "A-" and "-A". There might be a way to fix this in starterator, not sure, I will have to think on it.

As for recommendation I typically consider starts that are clearly that close on a starterator diagram as "the same" even if the computer gives them different numbers.

Chris

Edited 31 Jul, 2019 20:11
Posted in: Cluster DJ Annotation Tipsnew minor tail?
| posted 31 Jul, 2019 11:52
Jordan,
I would call this a minor tail protein. I would also call the longest ORF (start 17699). There is too much coding potential upstream of the 4th start. and the difference between start 1 &2 is negligible.
debbie
Posted in: Cluster DJ Annotation Tipsnew minor tail?
| posted 30 Jul, 2019 18:50
Jordan,
A good question, thanks for making it easy to check. I would call both Membrane proteins.
debbie
Posted in: Cluster D Annotation TipsHolin in D1
| posted 30 Jul, 2019 17:51
Jordan - I have a quick question (without looking) Are there any other membrane proteins in the region? If not, then it is acceptable to call this a holin.
If there are other proteins that could be the holins adjacent to these 2 genes, then i would leave it at membrane protein.
If it is more confusing that this and you want me to take a longer look, let me know.
debbie
Posted in: Cluster D Annotation TipsHolin in D1